WASHINGTON — The Department of Education is scaling back investigations into civil rights violations at the nation’s public schools and universities, easing off mandates imposed by the Obama administration that the new leadership says have bogged down the agency.

According to an internal memo issued by Candice E. Jackson, the acting head of the department’s office for civil rights, requirements that investigators broaden their inquiries to identify systemic issues and whole classes of victims will be scaled back. Also, regional offices will no longer be required to alert department officials in Washington of all highly sensitive complaints on issues such as the disproportionate disciplining of minority students and the mishandling of sexual assaults on college campuses.

The new directives are the first steps taken under Education Secretary Betsy DeVos to reshape her agency’s approach to civil rights enforcement, which was bolstered while President Barack Obama was in office. The efforts during Mr. Obama’s administration resulted in far-reaching investigations and resolutions that required schools and colleges to overhaul policies addressing a number of civil rights concerns.

That approach sent complaints soaring, and the civil rights office found itself understaffed and struggling to meet the department’s stated goal of closing cases within 180 days.

The office’s processing times have “skyrocketed,” the Education Department spokeswoman, Liz Hill, said, adding that its backlog of cases has “exploded.” The new guidelines were to ensure that “every individual complainant gets the care and attention they deserve,” she said.

In the memo, which was first published by ProPublica, Ms. Jackson emphasized that the new protocols were aimed at resolving cases quickly.

“Justice delayed is justice denied, and justice for many complainants has been denied for too long,” Ms. Hill said in a statement.

But civil rights leaders believe that the new directives will have the opposite effect. They say that Education Department staff members would be discouraged from opening cases and that investigations could be weakened because efficiency would take priority over thoroughness.

“If we want to have assembly-line justice, and I say ‘justice’ in quotes, then that’s the direction that we should go,” said Catherine Lhamon, who was the assistant secretary of the Education Department’s civil rights office under Mr. Obama, and who now heads the United States Commission on Civil Rights.

The commission — an independent, bipartisan agency charged with advising the president and Congress on matters of civil rights — voted on Friday to conduct a two-year investigation of federal civil rights enforcement, saying it had “grave concerns” about the Trump administration’s agenda. The commission identified the Education Department as an agency that was particularly troubling.

Nevertheless, the department’s move was lauded by advocates who believe that the office for civil rights has been overzealous in its enforcement activities in recent years.

Robert Shibley, the executive director of the Foundation for Individual Rights in Education, an advocacy group, said the measures will be welcomed on college campuses where the department has overstepped in carrying out sexual assault investigations. The organization is financially supporting a lawsuit against the department over a letter issued in 2011 directing campuses to change the burden of proof in cases of sexual assault.

“So many of the campus hearings are kangaroo courts with low due process, and you can’t really have any confidence in the outcomes,” Mr. Shibley said.

Both sides of the civil rights issue keyed on the department’s decision to reverse its practice of automatically broadening investigations and scrutinizing years of data, searching for patterns of violations.

The practice of systematic reviews, which Ms. Lhamon supported while leading the civil rights office, uncovered significant evidence of discrimination in school districts.

“It’s really a way of curtailing the way civil rights enforcement should be handled,” Ms. Lhamon said, reacting to the department’s new direction. “It’s literally a stick your head in the sand approach.”

For example, the department received a complaint that a black student at the Lodi Unified School District in California, about an hour south of Sacramento, received harsher punishment than a white student after the two were in a fight.

According to a published settlement agreement, the investigation found that schools with higher percentages of black students established stricter punishment for discipline incidents, and a review of four years of data revealed that black students across the district received disproportionately higher levels of discipline than white students.

But Mr. Shibley said the practice of systematic reviews was a significant burden, especially on colleges and universities, which sometimes had to review years of previous sexual assault complaints, and remedy anything they were found to have mishandled.

Since her appointment as the education secretary, Ms. DeVos has come under fire from lawmakers and civil rights advocates for her remarks about the department’s role in enforcing civil rights laws in the public school system.

The office is charged with enforcing legal prohibitions against discrimination by race, color, national origin, sex and disability.

Ms. DeVos has denounced discrimination in any form and has said schools that receive federal funds must follow federal laws. But she also believes in a limited federal role in education. She has signaled that her office is “not going to be issuing any decrees” on civil rights and that those should come from Congress or the courts.

In the memo issued last week, Ms. Jackson wrote that the department would “robustly enforce the civil rights laws under our jurisdiction, and we will do so in a neutral, impartial manner and as efficiently as possible.”

Ms. Jackson issued another internal memo last week about how her office would respond to cases of discrimination after the rollback of Obama administration rules that encouraged states to allow transgender students to use the bathroom corresponding to their gender identity.

Ms. Hill, the department spokeswoman, declined to release the internal document, but said it guides staff members on how to “functionally execute on these cases.” Transgender cases will be investigated by the department “fully and fairly” and will not be dismissed or referred because of a lack of guidance.

However, the office has indicated that it will also be more judicious in tackling complaints in general.

A version of this article appears in print on , on Page A19 of the New York edition with the headline: Education Dept. Plans to Scale Back Its Civil Rights Investigations. Order Reprints | Today’s Paper | Subscribe